Subsurface well tool control apparatus



Nov. 20, 1962 E. H. CLARK, JR., EI'AL 3,064, 3

SUBSURFACE WELL TOOL CONTROL APPARATUS Original Filed July 25, 1958 3 Sheets-Sheet l INVENTORS EEA/EST 11. Czaezxle. wL/fl/V ,D. Karyn/w By 100 MM M Nov. 20, 1962 E H. CLARK, JR, ET AL 3,064,738

SUBSURFACE WELL TOOL CONTROL APPARATUS Original Filed July 25, 1958 5 Sheets-Sheet 2 94 INVENTORS.

522M557- f1. CARE/6,17%. 2 ri/Lm/v D0 KE/Tfi/fil-l/V m MM Nov. 20, 1962 E. H. CLARK, JR., ET AL ,0 4,

SUBSURF'ACE WELL TOOL CONTROL APPARATUS Original Filed July 25, 1958 3 Sheets-Sheet 3 flaw 100 INVE R5. EI/QQNEST E 4 z, t/Z/u/wv D516 HAW 5 iwww United States Patent Ofiice 3,954,733 Patented Nov. 20., 1962 3,064,733 SUBSURFACE WELL TGGL CQNTRGL APPARATUS Earnest H. Clark, 51"., Downey, and Julian D. Keithahn, Anaheim, Calif., assignors to Baker Gil T Los Angeles, (Iaiih, a corporation oi 53a? nia Griginal application duly 25, 19 8, Ser. No. 759,951, new Patent No. 3,008,523, dated Nov. id, 1961. Divided and this application 1 oy. 14, E58, Ser. No. 773,552 1% Claims. (Ci. 1=6-23'7) The present invention relates to subsurface well bore equipment, and more particularly to control and clutch apparatus for determining the operation of the equipment in the well bore.

The present invention is a division of our application for Retrievable Well Packer and Anchor, Serial No. 750,951, filed July 25, 1958, now Patent No. 3,608,523.

An object of the invention is to provide a well tool adapted for operation in a well bore, and which includes an improved clutch or latch device for coupling parts of the tool together for joint longitudinal movement or for permitting relative longitudinal movement between the parts when the clutch or latch device is released.

Another object of the invention is to provide a clutch or latch device for controlling relative longitudinal movement between parts of a subsurface tool, the clutch device being adapted for disposition in a position precluding its inadvertent release during longitudinal movement of the tool in the well bore.

A further object of the invention is to provide a clutch or latch device for controlling longitudinal movement etween parts of a subsurface tool, the clutch device being in a clutched condition during lowering of the tool in the well bore and being precluded from inadvertent release during such lowering movement, the clutch device bein manipulated by the operator, whenever desired, to condition it for subsequent selective operation to place it in released or in clutching position.

This invention possesses many other advantages, and has other objects which may be made more clearly apparent from a consideration of a form in which it may be embodied. This form is shown in the drawings accompanying and forming part of the present specification. It will now be described in detail, for the purpose of illustrating the general principles of the invention; but it is to be understood that such detailed description is not to be taken in a limiting sense, since the scope of the invention is best defined by the appended claims.

Referring to the drawings:

FIGURE 1 is a combined longitudinal section and side elevation of the apparatus, with the clutch device in coupling position;

PEG. 2 is a longitudinal section through the apparatus shown in FIG. 1, with the clutch device in released condition;

FIG. 3 is a longitudinal section through the control sleeve portion of the apparatus;

FIG. 4 is a longitudinal section of a portion of the device, on an enlarged scale, with the parts in the position shown in FIG. 1;

FIG. 5 is a cross-section taken along the line 5-5 on FIG. 4;

FIG. 6 is a cross-section taken along the line 66 on FIG. 41;

FIG. 7 is a cross-section taken along the line "7-7 on FIG. 4;

FIG. 8 is an enlarged fragmentary longitudinal section of the control apparatus with the parts in the position shown in FIG. 2;

FIG. 9 is a cross-section taken along the line 9-9 on FIG. 8;

FIG. 10 is a cross-section similar to FIG. 9, with the clutch in a released position.

The control mechanism A is disclosed in the drawings as constituting part of a well packer or anchor, which is fully shown and described in the above-identified parent case; Only the lower portion of the apparatus is shown herein, which is adapted to be set against the well casing B as a result of downward movement of the central or main tubular body or mandrel 10 of the apparatus 7 with respect to the parts surrounding it. As described in the parent application, the tubular body or mandrel 10 is connectibie to a tubular string (not shown), such as tubing or drill pipe extending through the well casing B to the top of the well bore. It' is through manipulation of this tubular string and the body 10 of the tool that the control mechanism or clutch apparatus A is selectively placed in a clutching or an unclutching position.

The portion of the tool illustrated is adapted to anchor it against downward movement in the well casing. It includes a lower expander 55 having an external conical or expander surface 59 tapering in a downward and inward direction which is adapted to coact with companion inner tapered surfaces 60 on the anchor portion 61 of rocking types of slips 62 disposed in longitudinal grooves 63 in a slip ring 64 slidable relative to the body 10. Each slip 62 has a lower drag portion 65 urged outwardly into frictional engagement with the wall of the well casing B by one or a plurality of helical compression springs 66 mounted in each groove 63 and bearing against the base of the latter and against the drag portions 65 of the slips. The slips 62 are so designed that the springs 66 force the drag portions 65 into full fric-' its surface 59 will engage the anchor portions 61 and rock them outwardly into engagement with the tapered wall, the rocking action at first occurring about the upper part of the drag portion 65 of each slip.

The slips 62 are movable jointly downwardly in the casing by a retainer ring 68 mounted in external grooves 69 provided in the slips between their drag and anchor portions 65, 61, the upper end of this retainer ring being engaged by an outwardly directed flange 70 at the upper end of the slip ring 64. Thus, downward movement of the slip ring 64 will cause the flange 70 to engage-the ring 68, the latter engaging the lower sides of the slip grooves 69 to pull all of the slips 62 downwardly in the well casing. Joint upward movement of the slips 62 is provided by a stop ring 71 engaging their lower ends, this stop ring being suitably secured to the slip ring 64 by longitudinally extending screws 72. When the apparatus is out of the well casing, outward movement of the slips 62 is prevented by the retainer ring 68 and also by the lower terminals 73 of the slips engaging a stop rim 74 projecting upwardly from the stop ring 71. Separating movement between the expander 55 and slips 62 is limited by the longitudinal limit pins or screws 75 threaded in the lower expander 55 and received within bores 76 in the slip ring, the heads 77 of the screws engaging the upper ends of the bores or sockets 76, causing the lower expander '5 to pull upon the slip ring 64 and the slips 62 by virtue of the engagement of the screw heads 77 with the slip ring 64, while permitting the lower expander 55 to shift downwardly relative to the slips 62, since the screws 75 merely slide within the longitudinal bores 76 in the slip ring 64.

The lower expander 55 is shiftable downwardly relative to the lower slips 62 to anchor them against the well casing B in response to downward movement of the mandrel relative to the parts that surround it. The ability of the body or mandrel 10 to move downwardly to effect setting of the apparatus is governed by the control unit or clutch mechanism A at the lower part of the apparatus. As shown, such control unit includes an outer clutch housing 8 1 threadedly secured to the stop ring 71 and terminating in an inwardly directed flange 82. Contained Within the housing 81 is a control sleeve 83, the upper end of which is threadedly attached to the stop ring 71 and the lower end of which is attached as by pins 84 to a clutch sleeve or ring 85 having a recess 86 therein in which a dog or clutch element. 87 is located. This clutch element is urged inwardly by a compression spring 88 to place its upwardly facing wickers or teeth 89 in clutching engage ment with downwardly facing external wickers or teeth 90 formed on the exterior of the mandrel 10 along a substantial longitudinal length thereof and extending circumferentially therearound. When the clutch element 87 is engaged with the ratchet teeth 90 on the mandrel,

relative downward movement between the mandrel 10 and the clutch mechanism A surrounding it cannot occur. Since the clutch housing 81 is secured to the slip structure, the latter will move downwardly with the mandrel, relative downward movement of the mandrel 10 with respect to the expander 55 also being prevented in view of the fact that the slip sleeve 64 exerts a downward pull. on the lower expander 55 through the longitudinal screws 75.

When the clutch dog or element 87 is released from the ratchet teeth 90 on the mandrel, the latter can shift downwardly relative to the parts surrounding it, since downward movement of such latter part is resisted by frictional engagement of the drag portions 65 of the slips 62 against the Wall of the well casing. Release of the clutch element 87 is determined by a cam or key 92 having an upper head portion 93 which has a segment of a thread formed thereon threadedly meshing with internal threads 94 formed on the interior of the control sleeve 83. The key 92 is slidable relatively within a keyway 95 formed in the exterior of the mandrel 10.

The lower portion 96 of the key is a cam portion that extends outwardly beyond the ratchet teeth 90 on the body and which is adapted to engage the clutch dog 87 to cam it laterally outward from engagement with the body teeth 90. The lower end 97 of the cam 96 is tapered in a downward and inward direction so that it can engage the dog 87 and shift it outwardly as a' result of its downward movement along the control sleeve 83 and dog. The ends 98 of the dog are tapered or beveled to enable the cam portion 96 to engage the dog 87 rotationally and also effect its disengagement from the body ratchet teeth 90 against the force of its return spring 88. 7

Initially, the key or earn element 92 is disposed in an upper position with respect to the control sleeve 83, its threaded head engaging a. stop 99 at the upper end tion 94 of the sleeve.

of the control sleeve which limits the extent of the upward movement of the key relative to the control sleeve. The threaded interconnection between the key head 93 and the control sleeve 83 is a right-hand one such that right-hand rotation of the mandrel 10 and the key 92 will effect a downward feeding of the key along the control sleeve 83 to bring the cam portion 96 of the key downwardly to a position in which it can turn across the inner face of the clutch element 87 and cam it out of engagement with the ratchet teeth 90 on the mandrel. The extent of downward movement of the key is limited by engagement of its had 93 with a rotational stop element 100 extending across the lower end of the control sleeve thread 94. When the threaded head 93 of the key engages such stop element 100, the cam 96 is disposed fully across the clutch or dog element 87 to hold it disengaged from the teeth 90 on the mandrel, thereby allowing the mandrel 10 to move downwardly within the clutch housing 81.

Rotation of the mandrel 10 and key 92 in the opposite direction, or to the left, is limited after the key has threaded downwardly, to insure its disposition out of engagement with the clutch dog 87 to permit the ratchet teeth 89 on the latter to coengage with the ratchet teeth. 90 on the mandrel. This latter stop is in the form of a.

one-way acting element, such as a leaf spring 101 suitably secured to the control sleeve '83, as by' means .of a screw 102, the leaf spring being disposed in a sleeve opening 103 and extending inwardly of the threaded por- It will be noted that the leaf 7 spring 101 extends at an angle inwardly of the control.

sleeve 83 so that the key head 93 will engage the inner surface of the leaf spring, when rotated in a right-hand direction, and deflect the leaf spring outwardly, the head moving thereby and continuing its downward threading along the control sleeve 83 until the head 93 of the key engages the rotational stop at the lower end of the control sleeve 83. However, once the head 93;

has moved past the leaf spring 101, reverse rotation, or

rotation to the left of the key will cause it to engage the end 104 of the leaf spring, which will then prevent any further rotary movement of the mandrel 10 to the left relative to the control sleeve '83 and the clutch dog 87 carried within the clutch housing. Thus, the one-way leaf spring 101 will permit downward feeding of the key 92 along the control sleeve 83 to its dog camming' position, but will prevent upward threading therealong beyond the end 104 of the leaf spring 101 at which point the cam portion 96 is out of engagement with the clutch element 87. However, it can be turned in the right-hand direction back into engagement with the clutch element 87 to cam and hold such element out of engagement with the mandrel teeth 90. V

In the use of the apparatus within the well casing, its parts initially occupy the positions disclosed in FIGS. 1 and 4. The key 92 is preferably in its upper position along the control sleeve 83, the mandrel 10 being in its uppermost position. Since the key 92 is in its uppermost position it is substantially removed from the clutch dog 87 and cannot inadvertently release such clutch dog from clutching engagement with the mandrel 10. The spring 88 retains the clutch dog 87 in engagement with the mandrel 10, such that downward movement of the mandrel as a result of moving the tubular string (not shown) downwardly will cause the clutch mechanism A to move downwardly with the mandrel, pulling the slips 62 downwardly with it. Such downward movement of the slips will re- I sult in a downward pulling, through the screw 75, of the lower expander 55, which will exert a pull on other apparatus above the expander 55, which is illustrated and.

the slips preventing rotation of the apparatus surrounding the mandrel or body 10, including the control sleeve 83. As a result, the key 92 is turned by the mandrel relative to the control sleeve 83, when will cause the key to feed downwardly of the control sleeve and along the keyway 95 in the mandrel. The interconnecting thread between the key 92 and the control sleeve 83 may have a multiple pitch, such as a double pitch, so that only several revolutions are necessary to feed the key downwardly to the position in which it will move past the spring stop element 101 and fully into engagement with the lower rotational stop 100 on the control sleeve 33, at which time the cam portion 96 of the key will have cammed the dog 87 outwardly and will be disposed fully across the face of the dog, as shown in FIG. 2. The outer clutch portions are thereby disconnected from the mandrel 10, which will allow the mandrel to move downwardly relative to the parts surrounding it. Downward movement of the latter parts is prevented by the frictional engagement of the drag portions '65 of the slips 62 against the wall of the well casing B. Such downward movement will first result in actuation of some of the tool parts (not shown) above the expander 55, and described in the above-identified parent application, this expander then shifting downwardly relative to the slips 62, which are still prevented from moving downwardly by virtue of the frictional engagement of the slip drag portions 65 against the wall of the well casing. The expander will move behind the anchor portions 61 of the slips to rock them outwardly into anchoring engagement with the wall of the well casing about the upper ends of the drag portion 65 until the wickers 67 of the slips are embedded in the wall of the well casing.

Downward movement of the lower expander 55 cannot occur to any further extent. Accordingly, continued downward movement of the tubular string and the body will actuate other parts of the apparatus, as described in the above-identified parent application, to effect a full setting of the apparatus against the well casing.

The necessary operation can now be performed in the well casing, as described in the aforesaid parent application. After the operation has been completed, the slips '62 can be released from the well casing to permit the apparatus to be moved in the latter to a new operating position, or removed entirely from the well bore. To release the tool, it is merely necessary to move the mandrel 10 upwardly, which upward movement is permitted by the upward ratcheting of the body teeth along the teeth 89 of the clutch dog 87. The upward movement is transferred through upper portions of the apparatus (not shown) to the lower expander '55, pulling the latter upwardly relative to the slips 62, since upward movement of the slips is resisted by the frictional engagement of their drag portions 65 against the well casing. The upward movement of the expander will allow the spring 66 to rock the drag portions 65 of the slips back into full surface engagement with the wall of the well casing and their anchoring portions 61 out of engagement with the well casing. Upward movement of the lower expander 55 is transferred through the pulling screws or limit pins 75 to the slip structure and the surrounding clutch mechanism A, all of the parts then moving upwardly as a unit, with the drag portions 65 of the slips sliding frictionally along the wall of the well casing. The apparatus can now be elevated in the well casing and removed completely therefrom.

At any time after the apparatus has been released from the well casing it can be reset merely by turning the body 10 to the right to cause the cam 96 to again disengage the dog 87 from the ratchet teeth 99-. If the apparatus is to be moved to a lower position in the well casing B, then the tubular string (not shown) and the mandrel 10 connected thereto are turned to the left sufficiently to insure that the key 92 engages the end 104 of the spring or one-way stop member 101 which will insure that the dog is free to engage the mandrel, permitting the entire mechanism to be moved as a unit downwardly'in the well casing. Thus, the clutch A can be released and can be reclutched merely by appropriate turning of the tubular string and the mandrel 10, which will either position the cam 96 in contact with the dog, to disengage it from the ratchet teeth 99, or which will remove the cam from engagement with the dog, as determined by its contact with the end 1&4 of the spring 101, whereupon the dog spring 88 will urge the latter into engagement with the teeth 90 on the body to lock the parts together for joint downward movement in the well casing. However, prior to the initial setting of the apparatus in the well casing and during its lowering from the top of the well bore to the desired setting point in the well casing, inadvertent release of the clutch cannot occur since the key 92 is initially disposed a considerable distance above the dog 87 and its engagement with the dog will only take place as a esult of rotating the mandrel 10 and the key 92 a plurality of revolutions relaitve to the clutch mechanism that surrounds the mandrel.

The inventors claim:

1. In a well tool adapted for operation in a well bore: a body member connectible to a running-in string for moving the tool within the well bore; a clutch member slidable longitudinally on said body member; a clutch element movable laterally on one ofsaid members into engagement with the other of said members to couple said members for longitudinal movement together; cam means on said other of said members operable in response to relative movement between said members to engage and shit-t said clutch element laterally from coupling engagement with said other member; and means operatively associated with said cam means for shifting said cam means longitudinally of said clutch element between a position in which said cam means can engage and shift said clutch element from coupling engagement with said other member and a position in which said cam means cannot so engage and shift said clutch element.

2. In a well tool adapted for operation in a well bore: a body member connectible to a running-in string for moving the tool within the well bore; a clutch member slidable longitudinally on said body member; a clutch element movable laterally on one of said members and having clutch teeth; the other of said members having clutch teeth extending longitudinally therealong and adapted to mesh with said element clutch teeth to couple said members for longitudinal movement together; cam means on said other of said members operable in response to relative movement between said members to engage and shift said clutch element laterally from clutching engagement with the teeth on said other member to uncouple said members from each other; and means operatively associated with said cam means for shifting said cam means longitudinally of said clutch element between a position in which said cam means can engage and shift said clutch element from coupling engagement with said other member and a position in which said cam means cannot so engage and shift said clutch element.

3. In a well tool adapted for operation in a well bore: a body member connectible to a running-in string for moving the tool within the well bore; a clutch member slidable longitudinally on said body member; a clutch element movable laterally on one of said members into engagement with the other of said members to couple said members for longitudinal movement together; cam means on said other of said members operable in response to relative rotary movement between said members to engage and shift said clutch element laterally from coupling engagement with said other member; and means operatively associated with said cam means for shifting said cam means longitudinally of said clutch element between a position in which said cam means can engage and shift said element from coupling engagement with said other member in response to relative rotary movement betweensaid members and a position longitudinally to one side of said element in which said cam means cannot so engage and shift said element.

4. In a well tool adapted for operation in a well bore: a body member connectible to a running-in string for moving the tool within the well bore; a clutch member slidable longitudinally on said body member; a clutch element movable laterally on one of said members and having clutch teeth; the other of said members having a'plurality of clutch teeth extending longitudinally therealong and adapted to mesh with said element. clutch teeth to couple said members for longitudinal movement together; cam means on said other of said members operable in response to relative rotary movement between said members to engage and shift said clutch element laterally from clutching engagement from the teeth on said other member to uncouple said members from each other; and means operatively associated with said cam means for shifting said cam means longitudinally of said clutch element between a position in which said cam means can engage and shift said element from coupling engagement with said other member in response to relative rotary movement between said members and a position longitudinally to one side of said element in which said cam means cannot so engage and shift said element.

5. In a well tool adapted for operation in a well bore: a body member connectible to a running-in string for moving the tool within the well bore; a clutch member slidable longitudinally on said body member; a clutch element movable laterally on one of said members into engagement with the other of said members to couple said members for longitudinal movement together; cam means on said other of said members operable in response to relative rotary movement between said members to' engage and shift said clutch element laterally from coupling engagement with said other member; and interengaging'means on said cam means and one of said members for feeding said cam means longitudinally of said clutch element in response to relative rotation between said members between a position in which said cam means can engage and shift said element from coupling engagement with said other member and a position longitudinally to one side of said element in which said cam means cannot so engage and shift said element.

6. In a well tool adapted for operation in a well bore: a body member connectible to a running-in string for moving the tool within the well bore; a clutch member slidable longitudinally on said body member; a clutch element movable laterally on one of said members into engagement with the other of said members to couple said members for longitudinal movement together; cam means on said other of said members operable in response to relative rotary movement between said members to engage and shift said clutch element laterally from coupling engagement with said other member; means operatively associated with said cam means for shifting said cam means longitudinally of said clutch element between a position in which said cam means can engage and shift said element from coupling engagement with said other member in response to relative rotary movement between said members and a position longitudinally to one side of said element in which said cam means cannot so engage and shift said element; and means for preventing return movement of said cam means to one of said positions after it has been shifted from said one position to the other of'said positions.

7. In a well tool adapted for operation in a well bore: a body member connectible to a running-in string for moving the tool within the well bore; a clutch member slidable longitudinally on said body member; a clutch element movable laterally on one of said members into engagement with the other of said members to couple said members for longitudinal movement together; cam means on said other of said members operable in response to relative rotary movement between said members to engage and shift said clutch element laterally from coupling engagement with said other member;and interengaging threaded means on said cam means and said one of said members for feeding said cam means longitudinally of said clutch element in response to relative rotation between said members between a position in which said cam means can engage and shift said element from coupling engagement with said other member and a position longitudinally to one side of said element in which said cam means cannot so engage and shift said element. v

8. In a well tool adapted for operation in a Well bore: a body member connectible to a running-in string for moving the tool within the well bore; a clutch member slidable longitudinally on said body member; a clutch element movable laterally on one of said members into engagement with the other of said members to couple said members for longitudinal movement together; cam means on said other of said members operable in response to relative rotary movement between said members to engage and shift said clutch element laterally from coupling engagement with said other member; interengaging threaded means on said cam means and said one of said members for feeding said cam means longitudinally of said clutch element in response to relative rotation between said members between a position in which said cam means can engage and shift said element from coupling engagement with said other member and a position longitudinally to one side of said element in which said cam means cannot so engage and shift said element; and means for preventing return movement of said cam means to one of said positions after it has been shifted from said one position to the other of said positions. 7

9. In a well tool adapted for operation in a well bore: a body member connectible to a running-in string for moving the tool within the well bore; a clutch member slidable longitudinally on said body member; a clutch element movable laterally on one of said members into engagement with the other of said members to couple said members for longitudinal movement together; cam means on said other of said members operable in response to relative movement between said members to engage and shift said clutch element laterally from coupling engagement with said other member; and means operatively associated with said cam means for shifting said cam means longitudinally of said clutch ele ment from a first position in which said cam means cannot V engage and shift said clutch element from coupling en- I gagement with said other member to a second position in which said cam means is adapted to so engage and shift said clutch element.

10. In a well tool adapted for operation in a well bore: a body member connectible to a running-in string for moving the tool within the well bore; a clutch member slidable longitudinally on said body member; a clutch element movable laterally on one of said members into engagement with the other of said members to couple said members for longitudinal movement together; cam means on said other of said members operable in response to relative movement between said members to engage and shift said clutch element laterally from coupling engagement with said other member; means operatively associated with said cam means for shifting 'said cam means longitudinally of said clutch element from a first position in which said cam means cannot engage and shift said clutch element from coupling engagement with said other member to a second position in which said cam means is adapted to engage and shift said clutch element; and means for preventing return movement of said cam means to said first position after having been shifted to said second position.

11. In a well tool adapted for operation in a Well bore: a body member connectible to a'running-in string for moving the tool within the well bore; a clutch member slidable longitudinally on said body member; a clutch a 9 element movable laterally on one of said members into engagement with the other of said members to couple said members for longitudinal movement together; cam means on said other of said members operable in response to relative rotary movement between said members to engage and shift said clutch element laterally from coupling engagement with said other member; and interengaging means on said cam means and said one of said members for feeding said cam means longitudinally of said clutch element in response to relative rotation between said members between a first position in which said cam means cannot engage and shift said clutch element from coupling engagement with said other member and a second position in which said cam means is adapted to so engage and shift said clutch element.

12. In a well tool adapted for operation in a well bore: a body member connectible to a running-in string for moving the tool within the well bore; a clutch member slidable longitudinally on said body member; a clutch element movable laterally on one of said members into engagement with the other of said members to couple said members for longitudinal movement together; cam means on said other of said members operable in response to relative rotary movement between said members to engage and shift said clutch element laterally from coupling engagement with said other member; interengaging means on said cam means and said one of said members for feeding said cam means longitudinally of said clutch element in response to relative rotation between said members between a first position in which said cam means cannot engage and shift said clutch element from coupling engagement with said other member and a second position in which said cam means is adapted to so engage and shift said clutch element; and means for preventing return movement of said cam means to said first position after having been shifted to said second position.

13. In a well tool adapted for operation in a well bore: a body member connectible to a running-in string for moving the tool within the well bore; a clutch member slidable longitudinally on said body member; a clutch element movable laterally on said clutch member into engagement with said body member to couple said members for longitudinal movement together; cam means on said body member operable in response to relative movement between said members to engage and shift said clutch element laterally from coupling engagement with said body member; and means operatively associated with said cam means for shifting said cam means longitudinally of said clutch element between a position in which said cam means can engage and shift said clutch element from coupling engagement with said body member and a position in which said cam means cannot so engage and shift said clutch element.

14. In a well tool adapted for operation in a well bore: a body member connectible to a running-in string for moving the tool within the well bore; a clutch member slidable longitudinally on said body member; a clutch element movable laterally on said clutch member into engagement with said body member to couple said members for longitudinal movement together; cam means on said body member operable in response to relative rotary movement between said members to engage and shift said clutch element laterally from coupling engagement with said body member; and interengaging means on said cam means and said clutch member for feeding said cam means longitudinally of said clutch element in response to relative rotation between said members between a position in which said cam means can engage said element and a position longitudinally to one side of said element in which said cam means cannot so engage said element.

15. In a well tool adapted for operation in a well bore: a body member connectible to a running-in string for moving the tool within the well bore; a clutch member slidable longitudinally on said body member; a clutch element movable laterally on said clutch member into engagement with said body member to couple said mem bers for longitudinal movement together; cam means on said body member operable in response to relative rotary movement between said members to engage and shift said clutch element laterally from coupling engagement with said body member; interengaging means on said cam means and said clutch member for feeding said cam means longitudinally of said clutch element in response to relative rotation between a position in which said cam means can engage said element and a position longitudinally to one side of said element in which said cam means cannot so engage said element; and means on said clutch member engageable with said cam means to prevent its return movement to one of said positions after it has been shifted from said one position to the other of said positions.

16. In a well tool adapted for operation in a well bore: a body member connectible to a running-in string for moving the tool within the well bore; a clutch member slidable longitudinally on said body member; a clutch element movable laterally on said clutch member into engagement with said body member to couple said members for longitudinal movement together; cam means on said body member operable in response to relative movement be tween said members to engage and shift said clutch element laterally from coupling engagement with said body member; and means operatively associated with said cam means for shifting said cam means longitudinally of said clutch element from a first position in which said cam means cannot engage and shift said clutch element from coupling engagement with said body member to a second position in which said cam means is adapted to so engage and shift said clutch element.

17. In a well tool adapted for operation in a well bore: a body member connectible to a running-in string for moving the tool within the well bore; a clutch member slidable longitudinally on said body member; a clutch element movable laterally on said clutch member into engagement with said body member to couple said members for longitudinal movement together; cam means on said body member operable in response to relative rotary movement between said members to engage and shift said clutch element laterally from clutching engagement with said body member; and interengaging threaded means on said cam means and said clutch member for feeding said cam means longitudinally of said clutch element in response to relative rotation between said members between a position in which said cam means can engage said elelement and a position longitudinally to one side of said element in which said cam means cannot so engage said element.

18. In a well tool adapted for operation in a well bore: a body member connectible to a running-in string for moving the tool within the well bore; a clutch member slidable longitudinally on said body member; a clutch element movable laterally on said clutch member into engagement with said body member to couple said members for longitudinal movement together; cam means on said body member operable in response to relative rotary movement between said members to engage and shift said clutch element laterally from coupling engagement with said body member; and interengaging threaded means on said means and said clutch element for feeding said cam means longitudinally of said clutch element in response to relative rotation between said members between a first position in which said cam means cannot engage said clutch element and a second position in which said cam means is adapted to engage said clutch element.

19. In a well tool adapted for operation in a well bore: a body member connectible to a running-in string for moving the tool within the well bore; a clutch member slidable longitudinally on said body member; a clutch element movable laterally on said clutch member into engagement with said body member to couple said members for longitudinal movement together; cam means on said body member operable in response to relative rotary movement between said members to engage and shift 11 12 said clutch element laterally from coupling engagement tion after it has. been shifted-from said first position to with said body member; interengaging threaded means on said second position. said means and said clutch element for feeding said cam References Ciim in the file of this patent means longitudinally of said clutch element in response to relative rotation between said members between a first 5 UNITED STATES PATENTS position in which said cam means cannot engage said 2,753,943 Morean July 10, 1956 clutch element and a second position in which said cam 2,778,430 Baker Jan. 22, 1957 means is adapted to engage said clutch element; and 2,802,534 Conrad Aug.13, 1957 means on said clutch member engageable with said cam 2,806,536 Baker et a1. Sept. 17, 1957v 2,886,110 Baker May 12, 1959 means to prevent its return movement to said first posi- 2,988,149 Conrad June 13, 1961 

